Refrigerating apparatus



May 23, 1939- M. w. KENNEY REFRIGERATING APPARATUS Filed April 18, 1936 2 Sheets-Sheet 1 IIL.

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Ma/m Zulia@ @y @075 77?@0@ May 23,v 1939.- mA w. KENNEY l REFRIGERATING APPARATUS Filed April 18, 1935 2 Sheets-Sheet 2 vpsnnrms NEFmGERm/r Level.

Patented May 23, 1939 PATENT oFFicE nEr'mGEnA'rmG APPARATUS Mahlon W. Kenney, River Forest, Ill., assignor to General HouseholdvUtilities Company, Chicago, Ill., a corporation of Delaware Application April 18, 1936, serial No. A"15,932

13 Claims.

My invention relates in general to the art of refrigeration, and more particularly to refrigeration accomplished by means of the so-called compression evaporation cycle, wherein a. suitable fluid refrgerating medium is cyclically compressed in gaseous form, condensed to liquid form, and finally evaporated for the purpose of absc rbing heat, the invention having particular reference to the provision of an improved evaporator for use in such a system. The present application comprises a continuation in part of my co-pending jointapplication with Arthur R.

Constantine, Serial Number 734,076, for Refrigerating system.

An limportant object of the invention is to provide, in a refrigerant evaporator adaptedv to contain an evaporable liquid refrigerant therein and having a header chamber, a device for ejecting non-evapora-ble liquid from said evaporator comprising a receiver above the liquid levelin the header in position to catch liquid spattered above the said liquid level by violentebullition, whereby the non-evaporable liquid may be drained from the receiver and out of the evaporator; a further object being to form and arrange the evaporator to promoie spattering ebullition in the evaporator near said receiver.

`Another object is to form the evaporator with a gas exhaust outlet therein above the liquid level and to provide means for draining said receiver to said outlet; a further object being to arrange theevaporator with a' pair of headers and to mount the lgas outlet in the header containing the receiver. v

Another object `is to interconnect the headers by means of a conduit opening at its opposite ends above the liquid refrigerant level in said headers. A further object of the invention is to form the evaporator, in an inexpensive manner, by fastening together a pair of intertting plates having depressed portions forming refrigerant headers and ducts between the plates, when tted together.

A further object is'to emboss at least one of the evaporator forming sheets with a groove or grooves interconnecting said ducts intermediate the headers, and to form said grooves in position such that when the evaporator forming sheets are bent to form spaced apart Walls containing ,the headers, said grooves will provide registering Q inwardly extending heads on the facing surfaces' Q of said spaced walls and adapted to 'provide means for supporting objects to be cooled between said spaced walls. 55 A further object is to provide one ofthe bead (Cl. (i2- 126) forming grooves with a refrigerant inlet connection; a further object being to arrange the inlet connection to deliver liquid to a localized portion or portions of said bead opposite certain of the header connected ducts to promote vigor- 5 ous spattering ebullition therein.

These and numerous other objects and inherent advantages and functions of the invention will be apparent as the invention is more fully understood from the following description, which, 10 'taken in connection with the accompanying drawings, `discloses a preferred embodiment of my invention.

Referring to the drawings:

4Figure 1'is a perspective view of refrigeratlng l5 apparatus embodying my present invention as assembled in a cabinet to form a domestic refrig erator; Y

Figure 2 is a sectional view in horizontal section taken through the device shown in Figure 1;

Figure 3 is a diagrammatic sketch showing electrical connections forming a system for powering and controlling the operation of the refrigerating apparatus shown in Figure 1;

Figure 4 is a top plan view, partially in section, 25

of a refrigerant evaporator forming a part of the apparatus shown in Figure 1;

Figure 5 is'an end view of the evaporator shown in Figure 4;

Figure 6 is a sectional view taken substantially 30 along the line 6-6 in Figure 5; Vand Figure 7 is a sectional view through a float controlled expansion valve forming a part of the apparatus shown in Figure 1. P

To illustrate my invention, I have shown in 35 the drawings a refrigerating system. comprising a compressor ll, a condenser I3 and an evaporator l 5 connected togetherby suitable conduit means, including conduits 2| and 23 respectively, connecting the evaporator to form a refrigerant'cir- 40 culating system with the compressor and with the condenser. The circulating system provides means in which a refrigerating medium, in gaseous condition, may be drawn from the evaporator into and compressed in the compressor, andde- 45 livered thence to the condenser in which the compressed gaseous refrigerating medium may be liquefied as by cooling. The liquid refrigerant may be delivered from the condenser to the evaporator, preferably through an expansion device comprising, in the illustrated embodiment, a float controlled valve Il. The liquid refrigerant thus delivered in the evaporator at relatively low pressure boils and changes its state from liquid to gaseous condition withconsequent absorption of the possibility of ice accumulation through freezing of the .moisture in any of the conduits forming the circulating system.

'I'he float valve I1 is of simple construction comprising a cylindrical sheet metal shell IB forming side walls and an integral top, and a sheet metal cover portion I8 of generally semispherical configuration sealed to the lower opening of the cylindrical member I6 in order to form a sealed housing providing a float chamber, the cup-shaped member I8 having peripheral flanges 22 sealed to the edges of the open ends of the shell I6. At its upper end, the shell carries an inlet fitting comprising a nipple 24 sealed in an opening formed in the shell, the inner end of the nipple opening into the shell and carrying a lter element 26 preferably in the form of a wire screen. The outer end of the nipple 24 is threaded for connection with the conduit leading from the condenser, so that condensed liquid refrigerants may be delivered through the nipple and screen into the iioat chamber. The cup-shaped portion I8 is shaped to receive a preferably spherical oat member' 28 carrying 'a valve stem 32 .in position to enter a'channeled sleeve 34 which is sealed at one end in an opening located centrally in the bottom of the cup-shaped element I8, said element I8 having a strengthening ridge embossed therein around said opening. The channelled sleeve 34 provides a valve seat with which the valve stem 32 cooperates to provide -a control for the liquid refrigerant delivered from the oat chamber through the channeled sleeve 34. 'Ihe outer end of the sleeve 34 is provided for connecting with the conduit leading to the evaporator inlet. 'I'he cup-shaped portion I8 is also embossed outwardly as at 38 to facilitate the connection of supporting legsl |42 by which the casing forming the float chamber may be supported in operative position. As therlevel of liquid rises in the iioat chamber, the iloat 28 will be raised and will lift the valve stem in the sleeve 34 to permit liquid refrigerant to escape from the float chamber to the evaporator. The walls of the casing I6 are provided with an, annular inwardly extending groove to interttingly receive and support a corresponding grooved annular element 46 located within the float chamber in position to engage and limit the upward movement of the oat 28 therein, and thus prevent the possibility of the float rising to a height in the chamber permitting the valve stem 32 to escape'from the sleeve 34. l, v

I also nd it convenient to provide the Valve chamber with means permitting the introduction of the refrigeratlng medium into the system at this point. 'To this end the upper portions of the casing I6 are formed with a channeled iitting 48 sealed in an opening in the casing with its channel opening at one end into the oat chamber. The tting 48 outwardly of the float chamber is externally threaded to receive a cap 54 for sealing the ouer end of the channel. The outer v end of the channel is internally threaded to receive a valve 56, and the channel is formed with valve.

heat at the evaporator. The gaseous refrigerant a valve seat inwardly of the threaded portion adapted to be hermetically closed by screwing the valve 56 firmly against the seat. The valve 56 is provided with a channel which, when the valve 56 is raised from its seat, provides communication between the outer and inner ends of the fitting,

but which is so arranged that communication between the outer and inner ends of the fitting is cut oif when the valve is firmly seated.

The system may be loaded with the refrigerating medium by removing the cap 54 and valve element 56 entirely from the fitting 43. A refrigis inserted, but is not immediately seated. A` vacuum connection is then applied as by thread' ing the same upon the threads normally carrying-the cover cap 54. This vacuum connection preferably has meansmanually operable without removing the connection in order to seat the The vacuum connection is maintained for a suicient interval to withdraw from the system all air and moisture which has entered during the loading operation, the compressor during this air and moisture evacuation process, being preferably blanketed so that the system operates at a higherftemperature than would otherwise be the case, thus driving oil any air and moisture which may be dissolved or occluded in the lubricant and refrigerant. Since the lubricant is in liquid condition when it reaches the oat chamber, air and moisture will be drawn oif through the fitting 48 and the vacuum connection without abstracting any material quantity of the refrigerant.

Although the present invention is not necessarily restricted to a system embodied in domestic refrigeration, I have shown a refrigerating system arranged in a cabinet 50 of any suitable or preferred construction aifording a refrigerating compartment 58, in which the evaporator or heat absorber I5 is located. The compartment 58 pref# erably has heat insulating walls, and includes a frontal opening giving access to the compartment, a door or other closure member 60 being provided for said opening. The motor compressor unit, the condenser, vand condenser cooling means, and auxiliary apparatus for operating and controlling the same, need not necessarily be housed in the cabinet at all, but may be separately enclosed or located remotely from the cabinet, if desired.

I prefer, however, to provide the cabinet with a. mechanism compartment 62 adjacent and preferably immediately beneath the refrigerating compartment, and to house therein the compressor, condenser, and associated operating and control mechanism. The compressor, condenser, land asand 12 on opposite sides of the partition, and

within the walls of the mechanisml compartment, The apparatus carried by the support 64 when the same is assembled in the mechanism compartment, is located within the chamber-12 with the condenser I3 disposed in an opening 14 formed in the partition. The chamber 12 has an opening 16 through which air, blown into the chamber through the condenser andthe opening 14 by the blower 21, may escape from the cabinet. The opening 16 is' preferably in the bottom wall of the chamber 68, and the mechanism compartment has an opening, preferably in the rear wall off/the cabinet through which air may be drawn into the chamber 12, and around the compressor /and expelled thence through the condenser and the opening 14. The apparatus carriedon the panel 64 may be introduced in the mechanism compartment through said rear wall opening.

The compressor may be of any suitable or` convenient form, although I prefer to utilize a compressor powered by means of an electric motor 25the motor and compressor parts being enclosed in an hermetic casing to form a sealed unit having a refrigerant inlet connected by means of the conduit 2| with the evaporator and a compressJed refrigerant outlet connected with the condenser, a suitable medium for lubricating the operating parts of the motor compressor unit beingcontained'within the sealed casing of the unit.

A suitable motor compressor device is shown in my co-pending application, Serial No. 724,894, filed May 10, 1934.

The condenser I3 also may be of any suitable or preferred construction, preferably comprising a series of pipe coils formed with heat dissipating fins and arranged in a casing through which a cooling medium may be circulated past the pipe coils and fins for the purpose of absorbing heat from the condenser and the refrigerating medium passing therethrough. I prefer also to provide a suitable blower, preferably a fan, powered by an electric motor 21 by means of which air or other cooling fluid may be forced through the condenser for the purpose of cooling the same,

As heretofore mentioned, the refrigeration system of my present invention is particularly well adapted for use in domesticA refrigerators, for which reason I prefer to provide means for operating the .compressor driving and condenser cooling motor from a single vphase alternating current electrical power source, since power of this character is most usually available for the operation of domestic refrigerators. It is obvious, however, that the compressor driving and condenser cooling means may be of any suitable or preferred construction, but I prefer to utilize electricjmotors which ymay be 4operated and controlled simultaneously from-a common power source through a common control system, in order thus to avoid duplication of motor control elements. y'

To accomplish the foregoing, I have shown on lthe drawings in. Figure 3 a control system for machina The windings of each motor are connectedtogether at one end and to a'common conductor 33. Theopposite ends of the windings 29 of each motor are also connected together and to a common conductor 35, and the free ends of 'mercial or domestic power systems.

the windings 3| are connected togetherv and to a common conductor 31. The common conductor 33 is connected to a terminal 39 located within a casing 4| which houses a part of the electrical 4supply and control system. The terminal 39 is connected by means of a conductor 42, preferably forming a part of a cable 43 which extends from the casing 4| to a thermostat control casing 45 located adjacent the evaporator. 'I'he opposite ends of the cable 43 may be provided with detachableplug connectors v41 and 49 to facilitate the electrical connections necessary between the electrical elements in the casings 4| and 45.

The conductor 42 when the system is assembled for operation, forms a connection with one side of a switch preferably located in a casing 45, which switch is opened and closed by thermostatic means 5 2 including the-thermostat element 53, which extends in heat exchange relationship with the atmosphere adjacent the evaporator I5, so

v that the switch 5| may be operated in response to temperature conditions -prevailing in the. vicinity of the evaporator.

` at which the switch 5| will open or close.

The switch 5| is in series with a manually operable switch- 51, which also is or may be mounted.

on the casing 45, and which 'is connected lby means of a conductor 59, preferably forming a part of the cable 43 to a terminal 6| in the casing 4|. The terminal 5| is connected by means of a conductor, preferably forming a part of a cable 63, with means 55, preferably in the form of an electric plug of ordinary construction, adapted for removable insertion in a power outlet socket such as ls usually provided in com- 'I'he cable 53 has another conductor adapted for detachable which conductor connects with a terminal 61' within the casing 4|. This terminal 61 is in turn electrically connected with one end of a solenoid 59, also located within the casing 4|, the other end of which solenoid is connected with a `terminal 1| within the casing 4|. The terminal 1| is also connected with the common conducto-r 35.

When the device B5 is connected in an external circuit, power will be delivered between the terminals 6| and 41 to energize "a circuit extending between said terminals and including iri series the solenoid 59, the conductor 35, the windings 29 of the motors 21 and 25, the .common conductor 33, the conductor 42, the switches 5| and 51 and the conductor 59. This circuit, the Switches 5| and 51 being closed, will deliver electrlcal power to the windings 29 of both motora/60 which power will be substantially in phase with the power source.

The terminal 61 is also connected by means of a conductor 13 with one end of an inductionn coil 15, the other end of which is also connected through a condenser 11 with the conductor 13, the conductor induction coil and condenser being all housed within the casing 4|. The induction coil 15 has caps connected to stationary contacts 19 and 8| between which a shiftable blade 83 is movable in response to the current flowing through the solenoid 69. The blade 83 is electrically connected 4wi h the common conductor 31, and is adapted to se ctively connectth'e contacts 19 and 8| with said common conductor, and

thence to the windings 3| of the motors in relsponse to varying current flow in the solenoid 69.

It will thus be seen that the motor windings 3| are included in a circuit extending from the terminal 61 through the conductor 13, the condenser-induction coil system 15-11ne or other of the contacts 19, 8|, the conductor 31, the windings 3|, and thence through the conductors 33 and 4I, the switches 5| and 51, and the conductor 59 to the terminal 6|. The reactive systcm comprising the induction coil 15 and condenser 11 is adapted to shift the phase of the 'power-"applied to the windings 3|, so that these windings when so energized form with the windings 29, polyphase motor driving means.

The blade 83 is adapted to vary the reactive effect of the network comprising the induction coil 15 and the condenser 11. The motors pref.

erably employed are of the so-called capacitor induction motors, the windings comprising split phase windings adaptedv to be energized so that the motors may be started in operation from standstill position when energized with single phase alternating current applied between the terminals 6| and 61. It will be noted that both of the parallel circuits including the windings 29 and 3| are controlled by the switches 5| and 51, so that when the plug 65 is connected to a power outlet, the motors will remain inactive until both of the switches and 51 have been closed. The switch 51 being manually operable, affords manual control forthe motor while the switch 5I provides for automatic control, so that the motors and hence the refrigerating system, may be placed in operation automatically whenever the temperature in the vicinity of the evaporator rises above a predetermined value, which value may be determined by means of the knob 55.

When the plug 65 is connected with an external power source, alternating current will be delivered through the parallel circuits heretofore mentioned, which includes the several windings of the motors. The current delivered to the windings 29, however, will have a different phase relationship with respect to that delivered to the windings 3| because of the reactive effect, provided by the induction coil 15 and the condenser 11. In this Way a rotating field may be created in the motors for the purpose of starting the same.

At the instant' of' startingfthe switch 83 will engage one or other of the contacts 19, 8| in order that the proper phase relationship to start the motors will prevail in the current delivered to the windings. As the motors reach normal operating speed, the current flowing in the coils 69 will decrease, and the switch 83 will be moved under the influence of the solenoid, and will engage the other of said contacts 19, 8|, in order to alter the reactive effect produced upon the current flowing to the motor windings 3|, and thus to provide a desired phase relationship of current flowing in the windings for maximum operating emciency after the motors have reached normal operating speed.

The\ electrical system also includes-a circuit 85 containing a lamp 81, and a switch 89, said circuit being connected between the conductor 59 'of the cable 43, and another conductor 9| forming a part of said cable, and connected to the terminal 61, so that wheneverthe plug 65 is connected to the external power source, the lamp- 81 will be energized providing the switch 89 is closed. The lamp 81 is or maybe arranged in any suitable or convenient position within the refrigerator compartment, whilethe switch 89 is arranged to cooperate with the door giving access to the compartment. The door, when closed, is arranged to hold the switch 89 in open position, the switch closing to energize the lamp and illuminating the interior of the refrigerator compartment whenever the door is opened.

As heretofore mentioned, the motor-compressor unit, the condenser, condenser cooling motor, the float valve, the dehydrator, and the mechanism contained in the housing 4|, are mounted on the panel 64 for assembly as a unit in the mechanism compartment, while the evaporator and the control mechanism, supported in and by the casing 45, which is mounted on the evaporator, may be assembled as a unit in the refrigerating compartment 53. The cable 43 and the refrigerant conduits 2| and 23 are preferably built into the insulated walls of the cabinet in position to facilitate.

the necessary connections with the evaporator and the apparatus within the mechanism compartment after the same have been assembled in the cabinet. This arrangement/greatly simplifies the assembly of ther refrigerating system in the cabinet, and thus reduces manufacturing costs.

sheets are fastened together, the depressions and l grooves form spaced header chambers III and I I2 interconnected by a plurality of parallel ducts |04. The depressions |0I and |02 and the grooves I 03 are preferably formed in the sheet 91 and the other sheet 99 is assembled in position to overlie the depressions I0|. and grooves |03. the sheets being secured together as by curling the edge of one sheet. about the edge of the other. as shown at |05. and bv'welding around the peripheral edges of the sheets and between the grooves I 03 to form a closed refrigerant space defined. between the plates, by the header forming depressions and interconnecting grooves.

Thesheet 99. also. is preferably formed with depressions |01 and |09 in position respectively opposite the depressions IUI and-|02, so that the depressions IOI and |02 cooperate, in the evaporator unit, respectively, with the depressions |01 and |09 to form the elongated cylindrical header chambers and H2.v One of the sheets, preferably the sheet 99, is also formed at intervals with depressions or grooves II3, forming ducts II4 intersecting and commur icating with the ducts I 04.

After the formed sheets 91 and 99 hve been secured together in substantially at condition, they may be bent to provide a channel-shaped evaporator lelement having a cross-sectional configuration substantially as shown in Figure 5 of the drawings, and comprising spaced apart side walls I I5 and a bottom wall |I1, the side walls containing the header chambers, with the re frigerant ducts |04 extending beneath the header spaces in the side walls I|5 and in the bottom wall .I|1. `The ridges ||3 project inwardly of the facing surfaces of the walls I5, and form pairs of registering ridges on and betweenwhich objects to be cooled may be supported. In' Figure porting ridges ||3 to form an inlet header.

and may be bent to form flanges |23, which may be perforated as at |25 to receive supports by which the evaporator is hung or otherwise mounted within the refrigerating chamber 58.

Y The evaporator also is provided with an inlet connection for liquid refrigerant which is preferably positioned to deliver the refrigerant to the evaporator at a point below the lheaderchambers. To this end I utilize one of the shelf-sup- The ridge, so employed as an inlet header, is provided with an opening |25 at one end, and a tting. |21 having a channel |29 is secured to .the

. evaporator with one end of the channel in cornmunication with the header duct II4 dened by said ridge. ably threaded means I3| whereby the channel |29 may be connected with the conduit 23 through which liquid refrigerant is delivered from the compressor, -condenser and iioat valve. l'Ihe fitting |21 is, of course, firmly sealed on the evaporator toprevent the escape of the refrigerating medium from the systemat the point kof entry, and I prefer to provide a pipe |33 extending within the inlet header duct I|4 with one end ofthe pipe in communication with the channel |29 of the inlet fitting. The other end of the pipe |33 opens in the duct IM opposite one of the refrigerant ducts I 04 located substantially midway of the opposite ends of the evaporator, so that the refrigerant will enter the-evaporator at said centrally located duct. I prefer to position the inlet fitting at the end of the evaporator opposite the end at which the containers I I9v are introduced into and removed from the shelves I 2|, it being understood that the evaporator is mounted in the refrigerating compartment`with one end facingthe door to facilitate insertion and removal 'of objects through said door facing end. The inlet fitting also is preferably located entirely within the lateral confines of the evaporator walls in order to eliminate lateral projections. i

The evaporator is also provided with an outlet for evaporated refrigerant which outlet is also located Awithin the lateral confines of the evapo- 4rator walls and which preferably comprises a tting |35 secured in an opening formed preferably in the `sheet 99 at the header space III.

'I'he fitting |35 has an extension comprising a pipe or conduit |31 extending within the chamber III and having an end opening above the normal liquid refrigerant level therein. The pipe |31 communicates with a channel in the fitting' |35, and the fitting is formed with a preferably threaded portion |39 by means of which the channel may be connected with the refrigerant conduit 2| leading to the suction side of the compressor. The outlet fitting |35 may, of course,

The fitting is provided with preferthrough the outlet fitting, to the compressor. The connecting conduit |4| in addition to its gasified refrigerant conducting function, increases the strength and rigidity of the evaporator by assisting in holding the spaced walls ||5 rigidly in spaced relationship. The conduit |4| also provides a convenient handle for carrying the evaporator unit and holding the same in position while lit is being assembled in the cabinet.

When the evaporator is in operation in a refrigerating system, the level of the liquid refrigerant in the evaporator is normally maintained at an elevation in the headers as shown in Figure 5 of the drawings, the outlet lpipe |31 opening above said level. The refrigerating medium which I prefer to use in the system, comprises dichloromethane, and I prefer to operate the system under pressure conditions such that the liquid refrigerant entering the evaporator y will boil at the temperature prevailing in the vicinity of the evaporator, that is to say, within the refrigerating compartment. I prefer also to use a mineral oil for lubricating the compressor. This oil is insoluble in gaseous dichloromethane, but is soluble in the refrigerant when liquid. Even though lubricant is not soluble in dichloro-v methane when in gaseous condition, slight traces of the lubricant may escape from the compressor by entrainment with the compressed, gaseous refrigerant discharged to the condenser. The gaseous refrigerant liqueesin passing through the condenser, and the entrained lubricant will then dissolve in the refrigerant, and I have found in operation that the liquid refrigerant delivered from the condenser contains appreciable traces of .dissolved lubricant which is carried in'solution with the refrigerant into the evaporator. The lubricant does not, of course, evaporate at temperatures prevailing at the' evaporator, and since dichloromethaneand other refrigerants, which may be utilized in systems embodying my invention, have the capacity of dissolvinglubricant in any proportion, it will be apparent that, if no means is provided for extracting the dissolved lubricant from the evaporator, the lubricant in the system will eventually become concentrated in the evaporator and thus not only impair the lubrication of the compressor but also impair the eiciency of the evaporator. I consequently provide a lubricant separator and extractor which,

in the .illustrated embodiment, is formed as an integral part of the evaporator.

The lubricant separator and extractor may be of any suitable or preferred construction, and

I have shown an extractor comprising a strip of sheet metal |43 secured to the inner surface of Aone of the Ishells forming the evaporator to form a pocket |45, the strip |43 being secured to the shell portion at its opposite ends and along its lower edge, the upper edge of the strip being spaced from the shell. The strip |43 is formed with a struck-out portion |41 opposite and in position to overhang the inner end of the exhaust outlet |31. y

During the operation of the refrigerating apparatus the liquid in the header boils violently so that a certain vamount of liquid is continuously tossed upwardly Within the header and a portion drops into the pocket I 45. The vigorous ebullition is promoted by delivery of the liquid through the tube |33 into a localized portion of the groove ||3 at the end of the tube at one of the intersecting header connected, grooves |03 so that the introduction of cold refrigerant into the relatively Warmer liquid in the evaporator promotes vigorous boiling in said lduct and results in substantial spattering in the header adjacent the receiver |45. The liquidk may continue to boil in the pocket thus evaporating the refrigerant so that the pocket |45 becomes filled with liquid lubricant to the level of the struckmerous attendant functions and advantages will be understood from the foregoing: description; and it is obvious that numerous changes may be made in the form, construction and arrangement of the several parts of the illustrated appa-- lratus without departing from the spirit and scope of the invention, and without sacrificing any of its atte'ndant advantages, the embodiment herein shown being merely a preferred arrangement for the purpose of illustrating my inventive concept.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. An evaporator or boiler comprising a plurality of formed sheets welded together to form an evaporator space between the sheets, at least one of the sheets being embossed to form, with another of said sheets, a header chamber in the evaporator, at least one of the sheets being embossed to form a plurality of ducts opening at their ends in the header chamber, said evaporator being adapted to receive a body of evaporable liquid to a level in said header chamber and to receive the gases developed by ebullition of said liquid in said header chamber above the liquid level therein, means comprising a partition in said header dening a pocket therein on one side of said partition and opening upwardly in said header chamber above said ducts, in position to receive liquid spattered upwardly of the surface of the liquid in the header on the other side oi said partition due to ebullition of the liquid in said evaporator, said partition being formed to` provide an overflow, and an outlet in said header disposed in position with respect to said overow to receive liquid delivered from atid pocket through said overow into said out- 2. An. evaporator as set `forth in claim 1, wherein the overflow comprises a lip formed in tho partition.

3. An evaporator as set forth in claim 1, wherein the overow comprises a lip bent from the plane of the partition opposite said outlet.

4. An evaporator as set 'forth in claim 1,

wherein the overow comprises avlip bent from the plane of the partition between spaced slits formed therein.

5. An evaporator as set forth in claim 1, wherein the outlet comprises a channelled fitting in said header having an opening extending above the normal liquid level in the header and positioned beneath said overflow.

6. An evaporator or boiler comprising sheet metal means forming an evaporator space comprising. a header and a duct opening into the header, said evaporator being adapted to receive an evaporable liquid therein to a desired level in the header, extractor means comprising a receiver element disposed in said header in position facing upwardly above the liquid level therein and opposite said duct, and means for delivering an evaporable liquid into said duct at a point removed from said header whereby to produce vigorous ebullition of the liquid immediately beneath the receiver element.

'1. An evaporator or boiler comprising sheet metal means forming an evaporator space comprising a header and a duct opening into the header, said evaporator being adapted to receive 'an evaporable liquid therein to a desiredlevel in the header, extractor means comprising a receiver element disposed in said header in position facing upwardly above the liquid level therein and opposite said duct, means for delivering an evaporable liquid into said duct at a point removed from said header whereby to produce vigorous ebullition of the liquid immediately beneath the receiver element, a suction connection on said evaporator above the liquid level in said header, and means forming a conduit for draining liquid from the receiver element to said suc'- tion connection.

8. An evaporator or boiler comprising sheet metal means forming an evaporator space comprising an elongated horiontally disposed header and a duct extending downwardly of and, at its upper end, opening into the header intermediate the opposed ends of the header, said evaporator being adapted to receive an evaporable liquid therein to a desired levelrin the header, extractor means comprising a receiver element disposed in said header in position facing upwardly above the liquid level thereinand substantially opposite the upper end of said duct, and means for delivering liquid into the duct at a substantial distance below the header whereby to produce vigorous ebullition of the liquid immediately beneath said receiver element.

9. An evaporator or boiler comprising sheet metal means forming an evaporator space comprising spaced headers and a plurality of ducts opening at their opposite ends in the headers, said evaporator being adapted to receive an evaporable liquid therein to a predetermined level in said headers, extractor means in at least one of said headers comprising a receiver element disposed in position facing upwardly above the liquid level therein substantially opposite at least one of said ducts, and means for delivering liquid into the duct opening in said header opposite said receiver element whereby to produce p ment disposed in position facing upwardly above the liquid level therein substantially opposite at least one of said ducts, and means for delivering 'liquid into the duct opening in said header opposite said receiver element whereby to produce vigorous ebullition of the liquid beneath said receiver element, means interconnecting said headers above the liquid level therein, a suction connection on at least one of said headersabove the liquid level therein, and means for draining liquid from said receiveraelement into said exhaust connection.

vigorous ebullition of the liquid beneath said re- 11. An evaporator or boiler comprising a plurality of formed sheets secured together to form an evaporator space between the sheets, at least one of the sheets being embossed to provide a portion forming With another of said sheets a header in the evaporator, at least oneH of the sheets being embossed toform va.v plurality of ducts opening into the header, said evaporator being adapted to receive an evaporable liquid therein to a desired level in the header, extractor means .comprising a receiver element disposed in the header -in position facing upwardly above the liquid level therein and opposite certain of said ducts, and means for delivering an evaporable liquid into the -ducts at a point removed from said header whereby to produce vigorous ebullition of the liquid beneath the receiver element.

12. An evaporator or boiler comprising a pair of formed sheets -secured together to forman evaporator space therebetween, at least one ofthe sheets being embossed to provide a portionforming with the other sheet a header infthe evaporator, at least 4one oil the sheets being formed to provide a plurality of ducts opening in the header, and at least one of the sheets being formed with'a ridge intersecting said ducts for the purpose of interconnecting the same at points removed from the header, said evaporator being adapted to receive an evaporable liquid- .therein to a desired level in the header, extractor means comprising a receiver element disposed in said header in position facing upwardly above the liquid level therein and'opposite said ducts, and means for delivering an evaporable liquid Within said ridge and thence into said ducts whereby to produce vigorous ebullition of the the header, means forming a conduit extending in said ridge and opening therein opposite one of said ducts, said conduit having an end'projectingthrough an opening at an end o1' said ridge and a liquid inlet fitting connected to the projecting end of the conduit, said evaporator being adapted to receive an evaporable liquid.- therein to a desired level in the header, and ex-A tractor means comprising a receiver element disposed in said header in position facing upwardly above the liquid level therein and opposite the duct in which said conduit opens, whereby to produce vigorous ebullition of the liquid in the header immediately beneath the receiver element upon delivering the evaporable liquid through said conduit.

MAHLON W. KENNEY. 

